But Mary Ann Lancaster, a volunteer at the village community centre, said: “If it hadn’t been for him there would been buses and tankers going into the river. It would have been untold carnage.”

She added: “It was just a miracle that no more people were involved.”

Mr Pickering had set out before dawn to walk his dogs and draw out cash from an ATM at the Tesco branch across the river.

“When I came out of my house I could hear a big whooshing noise,” he recalled. “Then there was a big crash. When I got to the bridge I could see part of the handrail was missing.

“A bit further on I could see what looked like a puddle, but which I suddenly realised was actually the river running by where the bridge should have been.

“There was a car coming up behind me, so I flagged down the driver and got him to stop. I was dialling 999 while he did a three-point turn to get away.

“The 999 operator thought I meant the smaller bridge upstream, but I said no, it was the main bridge. She said she was sending some police officers out.

“By now the bridge was pitching and bucking, and I could see cracks in the stonework.

“There were two articulated wagons approaching the bridge so I stopped them too.”

In the gloom Mr Pickering could see a white van heading towards the southern end of the bridge. Its driver appeared to realise the severity of the situation and slewed into a position side-on so as to stop the single-decker bus and articulated lorry coming up behind him.

“I was shouting across the river: `Reverse the bus, reverse the bus!`”

PC Barker is thought to have reached that side of the bridge a few moments later, and began ushering the bus and lorry towards the Tesco loading bay.

On the other side of the river two other police officers – a WPC and PC Barker’s male colleague in the traffic unit – were asking Mr Pickering to move back so they could block off the bridge.

“I could see the officer I think was PC Barker. Behind him the lights of his vehicle were flashing.

“Suddenly there was a massive bang and the second section of bridge went in. It must have set up a domino effect because the rest fell in after it. Within a few seconds all the sections across the actual river had gone.”

Mr Pickering said the two police officers on his side of the bridge realised very quickly that their colleague had been swept away.

Despite this, they both carried on with the task of preventing other vehicles being driven onto the approach to the bridge.

“They both did brilliantly. The girl was unbelievable because she never left the top of that hill to the bridge.

“I could see she was upset and asked her if she was alright. She said `No, I think one of our colleagues has gone into the water”.

A few minutes later another officer arrived at the scene and began to console her.

Anne Wallace, 69, whose bungalow stands 20 yards from the riverbank, said: “It’s awful that the policeman died, but it could have been so much worse. At other times of the day there are scores and scores of people crossing that bridge.

“You get lots of children and their mums walking to Tesco and to the schools in Workington.”

Ken Russell, 73, a retired coastguard officer who lives nearby, said the Derwent brought huge quantities of debris downstream when it was in flood.

"In my time we used to keep the lifeboat tucked away because of the danger. I wonder whether some heavy debris like trees or sleepers were being banged against the centre arch, and that that’s what eventually gave way.”